Ricardo Barbosa, the Post Office Manager, looks at the destruction to the Carlstadt Post Office Thursday.

No one was in the store or post office when the fire broke out but two firefighters suffered minor injuries. One fell down the stairs and was treated at Hackensack University Medical Center and the other cut a finger.

A "minimal amount" of mail was in the post office at 331 First St. when the fire erupted and will be recovered and dried, Flood said. The day's mail had not yet been delivered to the post office and the previous day's mail had already reached homes and businesses.

The fire, reported after 1 a.m., started on the roof of MDR Electrical Supply Inc., which is above the post office. It took more than 60 firefighters about three hours to get the blaze under control. MDR Electrical Supply was heavily damaged and the water used to fight the fire flooded the post office below.

Firefighter try to bring the blaze at the Carlstadt post office building under control.

Neighbors told firefighters that workers had been on the roof on Wednesday, and Carlstadt Fire Chief Rob Popejoy said that the roofing materials could have ignited the fire.

Carlstadt’s building code inspector early this morning deemed the entire structure unsafe. Employees were allowed back in to retrieve some mail and anything salvageable, but the building will now be shut down.

Popejoy said wind gusts overnight fed the fire but the weather wasn’t much of an impediment to fighting it.